This image provided by the National Center for Missing & Exploited Children shows an undated photo of Avonte Oquendo. / AP

by Melanie Eversley, USA TODAY

by Melanie Eversley, USA TODAY

The Office of the New York City Medical Examiner has positively identified remains found in a river as those of an autistic teen who had been missing since October.

The disappearance of Avonte Oquendo, a severely austistic 14-year-old, had prompted a massive search effort. The remains were found in the East River on Friday morning, off the coast of Queens and near where he was last seen.

The confirmation was made Tuesday through DNA testing, said Julie Bolcer, spokeswoman for the medical examiner's office.

The office is doing further studies to determine the cause and manner of death, she said.

A Facebook page titled "Bring Avonte Home" thanked the public for its outreach and support during the search for Avonte.

"Please continue to keep his family in your thoughts at this tremendously difficult time," read a post on the page.

Avonte's disappearance prompted massive search efforts that included fliers plastered throughout the metro New York area. The aftermath of his disappearance included several possible sightings of the youngster, whose family said he was fascinated by trains.

A teen going for a walk near the Queens waterfront spotted the remains. Also found were a pair of Old Navy pants and Air Jordan sneakers that were the sizes and brands that Avonte was wearing when last seen.

The teen walked out of school in early October and did not return. He was seen on surveillance video walking toward a park along the East River on Oct. 4.

His parents said last week they were hopeful the remains did not belong to their son.